security: Match type size of unsigned
security: Match type size of unsigned

Error was observed on Tizen:RT

Change-Id: Ife95491d889ea573551c76f629ce562007f75527
Bug: https://jira.iotivity.org/browse/LITE-4
Signed-off-by: Philippe Coval <ff46fec9739d31cce915aabcc3a7a2c00eee4d6c@osg.samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/25251
Tested-by: IoTivity Jenkins <6267f6022d49a8a37a7fe97da24aebfab797522c@iotivity.org>
Reviewed-by: Kishen Maloor <c62ddea3cd661a9268bff15f07fc2229cdc9ac02@intel.com>

iotivity/iotivity-constrained,iotivity/iotivity-constrained,iotivity/iotivity-constrained,iotivity/iotivity-constrained